Carburetor



April 13 1926.

F. BRISCOE CARURETOR Filed March 5, 1919 5 .State of Michigan,

'20 improve the operationof 35 air conduit B extending which the cup D 'for the son,

' Patented lA-pr.'13, 1926.

yraam: nnisoon,

Baracca .Daviess may concern A To @nehme that 1I, FRANK Be it known Biusoon, a citi.-v -J zen of the United States of America, residing at Jackson, inthe county of Jackson and new and useful Y. Improvements in -Carburetors, of which the following is a specification, reference being had therein to the accompanying'.drawings.v

The invention relates -to carburetors of that'type in which the airis controlled by ahinged shutter extending obliquely across the air conduit to the extent of forming in ef-A fect aYenturi tube of variable open area,

15' into-operation with'means for discharging the liquid fuel into said Venturi tube and for variably metering the fuel by the movement creasedin area as the of said shutter.4 y

of the present invention to such 'carburetors by the 'introduction` f a dash-pot for controlling movement of the ai; shutter and fuel meteringl means. Audit is a further if is the object -object to obtaintlie improved results within construction. The iii-- comprises a-variousfea-- 25 out v complication vention, therefore, tures as hereinafter set forth.

In the drawings:

f Figure -1 is a; longitudinalseetion nfl-the 3 carburetor; Y A

' Fi re; '2 is '.a' similar view, showing a mod' edeonstruction; -f y i Fi re 3 iS-'a section on line 2.

A is the easingof a carburetor having the provided with a. depending hollow C to' chamber is al'lttachedely `thread -lower en d of the stem.'Y 1

the air conduit is' a f the' shutter which normality extends in inchned'positi'on across saidconduit .be'ing pivotally suppe vlower end 'and is sotted in the hollow uires provision of means for supplying the quid the hollowV stem mo ed at G. The arrangement is suchthat the reef incoming airjwill liftthe freeA the same about a Press .t

end of'the shutter, swinging le and thereby Aits pivot into a `lessaciite embracesthefree end iQf the's'hut'te'r so as to form a coupling engagement therewith-by which .the plunger will lbe liftedupon the have invented certain @same time liquid fuel is disc therethrough and fuel both oir ncxsoN, anoniem, assreNon, mr maSN'n ASSIGNMENTS, 'ro

roN'ruc, meinem, a coaromrroN oirj caminamos. imitation animen 3,1919. serai Nn. aaoss.

of the shutter, VThe head I has an Y opening aperture J therethrough which-is in alignvment with aslot K in the shutter, permitting a small `quantiy of air to pass theretliroughwhen the shutter is closed. The plunger-H is hollow, the chambertherein being sup lied with float cham `r D and a port L at the upper end of the plunger communicating with saidchamber dischar s 'rectly intothe re-` s tricted air port M is a screw adjustably engaging the head I -in alignment with the portA L and'which ma the liquid discharge The, plunger' H is .further provi liquid fuel from the.

be adjusted to vary through said port ded with a tapering side A N forming a`seeond'discharge for`the-liquid and which plunger is lifted.- Thus, when the shutter idling ition, the-passage of the air is vliquid fuel is dischar d into said passage through vthe restriete aperture L, however, theshutter F is opened creaseddiiferental airpressure actin'g therev011212110 all. I I iS enll is progressively int0 the restricted aperture J 'andthe and' at thev arged through is closed, as in the meteringjpassage in proportion to the volume Vof air.

The construction as thus far described has been heretofore'used and shutter F- and metering plunger beenjlifted by air pressure and returne gravity. 'To overcome 'the greater lag in the liquid, it is ing movement of the air means, such as-adash'- to introduce such an' e -plicating theconstruction.V I have, therefore, devised a construction avoiding such com lication, which is asfollowsz. 'l

e hollow 'plunger but it is diicult H is cl stemCastoforma dash-pot. This to the. interior of and to the metering'plnssage formed by the .tapered side N.' Bot .of these .results are ecomplished by formi-ngthe'hollow stem C with upper and lower portions plunger H v.and with' a channel' Oxbetween "said portions communicating through ports P with the liquid-fuel in` in operation the H have dJgy;

desirable to retard the open- "Y 'shutter by suitable.

ement without com- A fitting the i 'los thechamber. D. j

vThe channel O communicates with the interior of the hollow plunger H preferably through a series of ports Q, Q', etc., which aresuccessively registered with said channel as the plunger is lifted. There is also a port R vthrough the wall of the hollow plunger establishing 'communication between the interior thereof and the metering` through the ports R and metering passage VAdr Into. the air conduit. Inasmuch, however as the well within the hollow stem is filled with the liquid fuel the plunger cannot be moved without a displacement of the liquid.

Such displacement can ba effected either by providing ,a clearance between the vplunger and the hollow stem or by a restricted passage between the float chamber and the chamber below the stem. The latter construction is shown in Figure 2, in which S is a restricted passage through the wall of the hollowstem C leading from the float chamberV to a chamber T beneath the plunger H. This chamber is formed in.. a hollow member E which also forms the nut for clamping the cup D of the float chamber against a shoulder C on the hollow' stem C. ainage cock U may be attached to the member E' permitting the removal of water or sediment therefrom.

In the construction shown in Figure l instead of a restricted passage S a slight clearance is provided between the plunger H and the hollow stem C, so V'that leakage of the liquid through the clearance will permit' of the slow movement of the plunger.

To facilitate this construction and also form an easy method of producing the annular channel O, the hollow stem C is provided with a pair of bushings V and V. which are cast or otherwise secured therein respectively above and below the channel O. The upper bushing V may be made a comparatively close .fit to the portion of the plunger sliding therein, while the lowerl bushing 1s formedl with the desired clearance around the plunger that will permit the required displacement of the liquid.

With the construction above described the plunger H may be inserted into or removed from the hollow stem by providing an opening W in the upper side of the casing A, said'ropening being closed by a cap member W. This will facilitate the assembly of the parts and also adjustment of the same as required in setting the carburetor.

What I claim .as my invention is:

I n a carburetor, the combination with an air conduit, of a valve thereinfor restricting said conduit and opened by the pressure oi air passing therethrough, a cylindrical well beneath said conduit and opening thereinto, bushings in the upper and lower por- .tion of said well spaced from each -other to .form an annular channel therebetween, and I a hollowplunger extending fromfsaidfconduit into said well, beingconnected to said air valve to be operated thereby, said plungex.` being closed at its lower end, having a series of apertures intermediate its ends for estab lishing communication` between saidannular chamber and the interior of the plunger in different positions of adjustment thereof.

In testimony whereof I aiix my-signature. T

FRnNK museos. 

